W HO dares now doubt that e111- pirical science is the only legal- ly licensed hunter of truth and the one legitimate dispenser of informa- tion about reality ? Yet who but the scientists themselves can comprehend what science is saying r So a class of essaYIsts has grown up-they are almost the only surviving specimens of that delicate breed-that seeks to acquaint us with the astonishing facts revealed b) research and to place them In a per- spective that we might call philosophi- cal, did not the word itself embarrass us. Loren Eiseley, Desmond Morris, Annie Dillard, J oseph Wood Krutch, H. G. Wells-each of these, with his own special tone and own field of specialized knowledge, makes "sense" of the surreal scientific facts that loom beyond our lives like Oz, a benevolent kingdom ever recedIng into strange- ness, but one that now and then deigns to send us, in whimsical emission, a new immunity, or photographs of other planets. Dr. Lewis Thomas, whose essays for The New England Journal of ./.11 edicine have been col- lected as "The Lives of a Cell : Notes of a Biology Watcher" (Viking), is by profession a pathologist, by position the president of the MemorIal Sloan-Kettering Cancer Center in this city, and by avocation a lively, thoughtful writer. His field of expert knowledge, and of meditation, is the micro- cosm within the cell, bu t he also draws thoughts fron1 entomology and etymology, and believes that the best thing about the human race so far is Johann Sebastian Bach. V\T riting for hIS fel- low physicians and re- searchers, Dr. Thomas does not trouble to spare them hard words like "haptene," " k ." d " eu aryotIc, an myxo- tricha." In severa] essays he deals candidly with the practice of medicine. ("The great secret, known to in- ternists and learned early in marriage by internists' wives, but stin hidden from the general public, is that most things get better by themselves.") In other es- says, he tWIts the anthro- pologist C. M. Turnbull's BOOK5 A .LVew M elzorism dire report on the Ik, ruminates about C0111puters, dotes with surprising fervor on the intricacies of word derivations, lnd pars tribute to the Woods Hole Manne BIological Laboratory. But the collection as a whole IS by no means farraginous; it has a voice-awed yet optimistic, with little of Loren Eiseley's melancholy sense of inhuman vast- ness-and a theme The theme is, in a word, symbiosis. The first essay states, and several others remark upon, the fact that has impressed Dr. Thomas most: At the interior of our cells, driving them, providing the oxidative energy that sends us out for the improvement of each shining day, are the mitochondria, and in a strict sense they are not ours They turn out to be little eparate creatures, the colonial posterIty of migrant pro- karyocytes, probably primitive bacteria that s\varn into ancestral precursors of our eukaryotic cells and stayed there. Ever since, they have maintained themselves and their ,vays, replicating in their 0'" n fashion, privately, "Tith their o\vn D::\A and Ri\A quite different from ours. They are as much sym bionts --- Zi: 83 as the rhizobial bacteria in the root of beans. Sin1ilarly, chloroplasts in plante; al e "independent and self-replicating lodg- ers;" the flagellae that propel mYÀo- tricha turn out to be fully formed spi- rochetes that have tidily attached them- selves; the enzyme-prod ucing colonies in the digestive tracts of many animals illustrate "metIculously symmetrIcal symbiosis;" giant clams possess small lenses in their tissue that focus sunlight for the engulfed, symbiotic algae. The moral seems plain: "There is a tend- ency for living things to join up, es- tablish linkages, live inside each other, return to earlier arrangements, get along, whenever possible. This is the \vay of the world." Most diseases result from ovel reaction on the part of the bodj'<; defenders, "a biologic misintel- pretation of borders." Apparently ma- l 1 . (( èVO ent mIcro-organIsms turn out on clos<: eÀaIninatÍon to be rather more like bystanders." "Pathogenicity is not the rule.... There is nothing to be gained, in an evolutionary sense, by the C- 6---? \ ((Salad, beer, and cold cuts in the fridge. Back around etght Love Helen."